Cisco Certified Design Associate (CCDA) is an associate-level credential going right after the entry-level CCENT certification. The CCDA curriculum focuses on design objectives and methodologies, routing and addressing protocols, and network extension reviews within data center, basic campus, voice, wireless, and security networks. This certificate is intended for Network Design Engineers, Sales Engineers, and System Engineers who should have the relevant skills to build, design and validate a secure Cisco network. Becoming a CCDA is an appreciable first step to a lucrative and exciting career of a network engineer or network designer. As a CCDA certified specialist, you will be able to design switched and routed network services and infrastructures including WAN, LAN, and broadband access. The CCDA certification is valid for 3 years.